Over the years various types of fittings have been developed for use in conjunction with inflatable members such as flotation bags for helicopters. In general, it is necessary that a fluid be delivered from a high pressure, small volume source to the inflatable member on a selected basis when the system is energized. In order to provide rapid uniform inflation of such inflatable members it is common to provide a plurality of fittings on each inflatable member to permit the simultaneous introduction of fluid such as a compressed gas to a number of different areas within the inflatable member. In order to effect such distribution of fluid input through various fittings, one fitting is commonly connected to the pressurized fluid source by a conduit and additional conduits interconnect to the other fittings. Since the configuration of the inflatable member normally changes drastically from an uninflated stored configuration to the inflated operating condition, it is necessary to provide for movement of the position or orientation of the conduits or hoses as by providing swivel elements on the fittings to accommodate random repositioning of the conduits. Since the conduits may be and normally are left in position after the inflation, the possibility of further conduit or hose movements relative to the inflatable member must also be provided for to avoid undue stresses which could be deleterious to the combined fabric and elastomeric make up of such inflatable members.
Swivels of this type have normally been constructed of stainless steel or brass to accommodate high operating pressures over a brief time and corrosion resistance in a salt water environment despite cost and weight disadvantages they provide in an aircraft environment. The prior art devices have generally employed a type of poppet valve as the primary operating component of the fittings. In order to provide an effective seal after inflation, the poppet valves are commonly provided with a molded elastomeric surface to achieve an effective seal. Normally elastomers which can be molded on a valve surface have limited resistance to the distortions and pitting which can be produced by the passage of high velocity fluid.
The throttling effect produced by conventional fittings is normally predicated upon the size of a plurality of passages positioned between the poppet valve and the inflatable member. Depending upon the interconnection and spacing between the various fittings and the pressurized source of fluid it is normally necessary to have available a plurality of different fittings having different sized passages to achieve a system balance which accommodates a division of the fluid from the pressurized source to the various fittings. In employing fittings of this nature, the necessity for varying system balance, e.g., to use different pressurized fluid sources, normally requires replacement of the entire fitting. To applicant's knowledge one or more of the above outlined disadvantageous structural or operational features have accompanied prior art devices of this type.